Reduced level of physical activity in Japanese patients with chronic obstructive pulmonary disease

Correlation between frailty and reduction in cortical thickness in patients with chronic obstructive pulmonary disease

Physical inactivity and cognitive impairment in patients with chronic obstructive pulmonary disease (COPD) can lead to frailty and poor prognoses. However, little is known regarding the association between frailty and the human brain. We hypothesized that the brain structure could change according to frailty in patients with COPD and focused on cortical thickness. Cortical thickness measured by magnetic resonance imaging and frailty scores using the Kihon Checklist (KCL) were assessed in 40 patients with stable COPD and 20 healthy controls. Among the 34 regions assessed, multiple regions were thinner in patients with COPD than in healthy individuals (p < 0.05). We found significant negative correlations between the eight regions and the KCL scores only in patients with COPD. After adjusting for age and cognitive impairment, the association between the left and six right regions remained statistically significant. The correlation coefficient was the strongest in the bilateral superior frontal gyrus (left: ρ = - 0.5319, p = 0.0006) (right: ρ = - 0.5361, p = 0.0005). Interestingly, among the KCL scores, the daily activity domain showed the strongest correlation (sensitivity, 90%; specificity, 73%) with the bottom quartile of the reduction in the superior frontal gyrus. Frailty in patients with COPD is associated with a thickness reduction in the cortical regions, reflecting social vulnerability.

Impacts of regular physical activity on hospitalisation in chronic obstructive pulmonary disease: a nationwide population-based study

INTRODUCTION

Studies that comprehensively evaluate the association between physical activity (PA) levels, particularly by quantifying PA intensity, and healthcare use requiring emergency department (ED) visit or hospitalisation in patients with chronic obstructive pulmonary disease (COPD) are limited in Korea.

METHODS

The risk of all-cause and respiratory ED visit or hospitalisation according to the presence or absence of COPD and the level of PA was evaluated in a retrospective nationwide cohort comprising 3308 subjects with COPD (COPD cohort) and 293 358 subjects without COPD (non-COPD cohort) from 2009 to 2017.

RESULTS

The COPD group exhibited a higher relative risk of all-cause and respiratory ED visit or hospitalisation across all levels of PA compared with the highly active control group (≥1500 metabolic equivalents (METs)-min/week). Specifically, the highest risk was observed in the sedentary group (adjusted HR (aHR) (95% CI) = 1.70 (1.59 to 1.81) for all-cause ED visit or hospitalisation, 5.45 (4.86 to 6.12) for respiratory ED visit or hospitalisation). A 500 MET-min/week increase in PA was associated with reductions in all-cause and respiratory ED visit or hospitalisation in the COPD cohort (aHR (95% CI) = 0.92 (0.88 to 0.96) for all-cause, 0.87 (0.82 to 0.93) for respiratory cause).

CONCLUSIONS

Compared with the presumed healthiest cohort, the control group with PA>1500 METs-min/week, the COPD group with reduced PA has a higher risk of ED visit or hospitalisation.

Physical activity and outcomes in Japanese patients with chronic obstructive pulmonary disease: From the Ishinomaki COPD Network registry

BACKGROUND

Low physical activity levels are associated with an increased risk of exacerbations and all-cause mortality in patients with chronic obstructive pulmonary disease (COPD); however, evidence is limited in a population with a low frequency of exacerbations, such as the Japanese population. This study investigated the effects of physical activity on outcomes in Japanese patients with COPD.

METHODS

We conducted a prospective observational study in a cohort of Japanese patients with COPD between April 2018 and July 2020. Characteristics, frequency of exacerbations, and mortality were assessed during the 1-year follow-up period. Logistic regression analysis evaluated the relationship between physical activity and outcomes.

RESULTS

A total of 309 patients (294 males; median age, 75 years) with stable COPD were included, and 307 completed follow-up. Patients with lower levels of physical activity were older, and showed increased airflow obstruction, limited exercise capacity, increased dyspnea, depressive state, poor health status, muscle weakness, and more information needs for the disease. Patients with high levels of physical activity had a lower risk of exacerbation, including hospital admission, compared to those with low levels of activity (odds ratio [OR], 0.46; 95 % confidence interval [CI], 0.22-0.97; and OR, 0.21; 95 % CI, 0.09-0.50, respectively). High physical activity was associated with a reduced risk of all-cause mortality (OR, 0.07; 95 % CI, 0.01-0.55) and respiratory mortality (OR, 0.16; 95 % CI, 0.02-1.47).

CONCLUSIONS

These findings showed that higher physical activity is associated with better clinical outcomes, even in a COPD population with a low frequency of exacerbations.

Effects of Pedometer-Based Step-Feedback on Physical Activity of Severe COPD Patients

Purpose

This study investigated whether adding step-feedback (step-FB) from a pedometer to pulmonary rehabilitation (PR) programs could increase the physical activity (PA) of low-activity patients with severe chronic obstructive pulmonary disease (COPD).

Patients and Methods

We included low-activity patients with severe COPD (step-FB group: 14 patients; control group: 17 patients) who underwent PR for the first time. The usual PR program for patients with severe COPD consisted of two 8-week sessions (PR session 1: PR1, PR session 2: PR2). The step-FB group was provided a program with step-FB added to PR2 (PR2+step-FB). Furthermore, all patients were evaluated at pre-intervention (baseline), PR1, and PR2. The primary outcome of this study was the number of daily steps (steps) and energy expenditure from activity (energy expenditure), as measured by a pedometer. The secondary outcomes were dyspnea and exercise tolerance.

Results

In PR1, dyspnea, exercise tolerance, steps, and energy expenditure were significantly improved as compared to baseline, in both groups. During PR2, dyspnea and exercise tolerance were significantly improved as compared to PR1, in both groups. Steps and energy expenditure were significantly improved in the step-FB group, but not in the control group.

Conclusion

PR improved PA by improving physical function in severe COPD patients. Adding step-FB improved PA in severe COPD patients by presenting an activity goal for improving PA. Therefore, pedometer-based step-FB is a viable addition to PR and has the potential to improve PA continuously in these patients.

Prospective Real-World Analysis of Asthma Patients With Preserved and Reduced Physical Activity

BACKGROUND

Asthma is a highly heterogeneous airway disease, and the clinical characteristics of patients with asthma with preserved and reduced physical activity are poorly understood.

OBJECTIVE

We aimed to investigate the risk factors and clinical phenotypes associated with reduced physical activity in a wide range of patients with asthma.

METHODS

We conducted a prospective observational study of 138 patients with asthma, including patients with asthma without chronic obstructive pulmonary disease (COPD) (n = 104) and asthma-COPD overlap (n = 34), and 42 healthy controls. Physical activity levels were measured for 2 weeks using a triaxial accelerometer at baseline and 1 year later.

RESULTS

Higher eosinophils and body mass index (BMI) were associated with reduced physical activity in patients with asthma without COPD. Cluster analysis of asthma without COPD revealed 4 asthma phenotypes. We identified a cluster with preserved physical activity (n = 43) that was characterized by good symptom control and lung function and included a high proportion of biologics users (34.9%). Multivariate regression analysis revealed that patients with late-onset eosinophilic (n = 21), high-BMI noneosinophilic (n = 14), and symptom-predominant asthma phenotypes (n = 26) had lower levels of physical activity than controls. Patients with asthma-COPD overlap also had significantly lower physical activity levels than controls. Similar trends in physical activity levels were observed in each asthma group at 1-year follow-up.

CONCLUSION

This study showed the clinical features of patients with asthma with preserved and reduced physical activity. Reduced physical activity was observed in various asthma phenotypes and in asthma-COPD overlap.

Determinants of Activity Phenotype in Patients with Chronic Obstructive Pulmonary Disease

Introduction

Physical activity (PA) and sedentary behavior (SB) have attracted attention in chronic obstructive pulmonary disease (COPD), and there have been efforts to evaluate PA and SB separately. The factors associated with the characteristics of the four activity phenotypes defined by the durations of PA and SB are largely unknown. The aim of this study was to clarify the factors that could differentiate each activity phenotype.

Materials and Methods

Study subjects were outpatients with stable COPD who were ≥40 years of age. We investigated the influence of 26 different factors on the activity phenotypes of COPD and extracted the factors that showed significant differences among the four activity phenotypes.

Results

Two hundred sixteen patients were included in the analysis. Exercise capacity and dyspnea were determinants that distinguished the low PA groups from the high PA groups. The pulmonary function and desaturation during exercise were factors that distinguished the high PA with low SB group from the low PA with high SB group. BMI, grip strength, upper arm circumference and HbA1c were higher in the low PA and low SB group than in the low PA and high SB group.

Conclusion

These factors could be the determinants discriminating activity phenotypes of patients with COPD.

Objective Measurement of Physical Activity and Sedentary Behavior in Patients with Chronic Obstructive Pulmonary Disease: Points to Keep in Mind during Evaluations

Objective measurement methods using accelerometers have become the mainstream approach for evaluating physical activity (PA) and sedentary behavior (SB). However, several problems face the objective evaluation of PA and SB in patients with chronic obstructive pulmonary disease (COPD). For example, indicators of PA differ depending on whether the accelerometer detects the kind of activity on the one hand, or its intensity on the other. Measured data are also strongly influenced by environmental factors (weather, season, employment status, etc.) and methodological factors (days with uncommon activities, non-wearing time, minimum required wearing time per day, minimum number of valid days required, etc.). Therefore, adjusting for these factors is required when evaluating PA or SB, especially when evaluating the effects of intervention. The exclusion of sleeping time, unification of total measurement time, and minimization of the required wearing time per day might be more important for the evaluation of ST than for evaluating PA. The lying-down-time-to-sitting-time ratio was shown to be larger in COPD patients than in healthy subjects. In this review, we clarified the problems encountered during objective evaluations of PA and SB in patients with COPD and encouraged investigators to recognize the presence of these problems and the importance of adjusting for them.

Distinct contributions of muscle mass and strength stratified by nutritional status to physical activity in patients with chronic obstructive pulmonary disease

BACKGROUND

Physical activity is one of the most important prognostic factors for patients with chronic obstructive pulmonary disease (COPD). Physical activity correlates significantly with skeletal muscle mass and strength. Pulmonary rehabilitation has been conducted to improve physical activity, but its effectiveness has been inconsistent. Nutritional status is also related to physical activity in patients with COPD. The relationships between skeletal muscle mass, strength, and nutritional status evaluated using the Mini Nutritional Assessment Short Form (MNA-SF) were investigated. How nutritional status alters the relationships between physical activity, exercise capacity, skeletal muscle mass, and strength was also investigated.

METHODS

This retrospective, cross-sectional study enrolled 81 outpatients with COPD. In all patients, physical activity, exercise capacity, body composition assessment, and MNA-SF were assessed. The relationships between physical activity, exercise capacity, skeletal muscle mass, and strength were examined according to the MNA-SF.

RESULTS

The MNA-SF high group had significantly higher skeletal muscle mass than the MNA-SF low group when skeletal muscle strength was the covariate. In the MNA-SF low group, physical activity positively correlated with skeletal muscle mass. In the MNA-SF high group, physical activity positively correlated with skeletal muscle strength.

CONCLUSIONS

This study showed that the nutritional status of patients with COPD alters the relationship between physical activity and skeletal muscle mass or strength. Optimizing rehabilitation with nutrition interventions according to nutritional status might improve physical activity in patients with COPD.

Computed Tomography Lung Density Analysis: An Imaging Biomarker Predicting Physical Inactivity in Chronic Obstructive Pulmonary Disease: A Pilot Study

Physical inactivity correlates with poor prognosis in chronic obstructive pulmonary disease (COPD) and is suggested to be related to lung hyperinflation. We examined the association between physical activity and the expiratory to inspiratory (E/I) ratio of mean lung density (MLD), the imaging biomarker of resting lung hyperinflation. COPD patients (n = 41) and healthy controls (n = 12) underwent assessment of pulmonary function and physical activity with an accelerometer, as well as computed tomography at full inspiration and expiration. E/I_MLD was calculated by measuring inspiratory and expiratory MLD. Exercise (EX) was defined as metabolic equivalents × duration (hours). COPD patients had higher E/I_MLD (0.975 vs. 0.964) than healthy subjects. When dividing COPD patients into sedentary (EX < 1.5) and non-sedentary (EX ≥ 1.5) groups, E/I_MLD in the sedentary group was statistically higher than that in the non-sedentary group (0.983 vs. 0.972). E/I_MLD > 0.980 was a good predictor of sedentary behavior in COPD (sensitivity, 0.815; specificity, 0.714). Multivariate analysis showed that E/I_MLD was associated with sedentary behavior (odds ratio, 0.39; p = 0.04), independent of age, symptomology, airflow obstruction, and pulmonary diffusion. In conclusion, higher E/I_MLD scores are associated with sedentary behavior and can be a useful imaging biomarker for the early detection of physical inactivity in COPD.

Clinical Impacts of Interventions for Physical Activity and Sedentary Behavior on Patients with Chronic Obstructive Pulmonary Disease

Recently, physical activity has increasingly become the focus in patients with chronic obstructive airway disease (COPD) because it is a strong predictor of COPD-related mortality. In addition, sedentary behavior, which is included as a category of physical inactivity including such behaviors as sitting or lying down, has an independent clinical impact on COPD patients. The present review examines clinical data related to physical activity, focusing on the definition, associated factors, beneficial effects, and biological mechanisms in patients with COPD and with respect to human health regardless of COPD. The data related to how sedentary behavior is associated with human health and COPD outcomes are also examined. Lastly, possible interventions to improve physical activity or sedentary behavior, such as bronchodilators and pulmonary rehabilitation with behavior modification, to ameliorate the pathophysiology of COPD patients are described. A better understanding of the clinical impact of physical activity or sedentary behavior may lead to the planning of a future intervention study to establish high-level evidence.

Validation of Simple Prediction Equations for Step Count in Japanese Patients with Chronic Obstructive Pulmonary Disease

Physical activity is decreased in patients with chronic obstructive pulmonary disease, and decreased physical activity leads to a poor prognosis. To determine an individual’s target step count from the measured step counts and predicted step counts, simple and detailed prediction equations for step count were developed. To verify the validity of the simple prediction equation, the validity of the simple equation was evaluated in a different cohort and the correlation between the step counts calculated by the simple equation and those by the detailed prediction equation were evaluated. When the step counts calculated by the simple prediction equation for all participants were compared with the measured step counts, a significant correlation was obtained among them, and the calculated values were found to be reproducible with the measured values in patients with a measured step count of <6500 by Bland−Altman plots. Furthermore, the values calculated by the simple prediction equation and those calculated by the detailed prediction equation showed a significant correlation. In conclusion, the simple prediction equation was considered reasonable.

Impact of non-exercise activity thermogenesis on physical activity in patients with COPD

Physical inactivity is associated with comorbidities and mortality in chronic obstructive pulmonary disease (COPD) patients. Although non-exercise activity thermogenesis (NEAT) is important for evaluating the physical activity level (PAL) of patients with chronic diseases, it has not yet been assessed in COPD patients. This study included male patients with COPD (n = 28) and high risk for COPD (n = 8). Total energy expenditure (TEE) and basal metabolic rate (BMR) were measured using the doubly labeled water (DLW) method and indirect calorimetry, respectively. PAL was calculated as TEE/BMR, while the NEAT was obtained from a questionnaire. Physical activity was also assessed using an accelerometer. The total NEAT score was correlated with PAL (r = 0.534, P < 0.001), while PAL was correlated more strongly with the non-locomotive NEAT score (r = 0.548, P < 0.001) than the locomotive NEAT score (r = 0.278, P = 0.10). Regarding accelerometer-obtained data, this questionnaire mainly reflected steps/day and the duration of light locomotive and non-locomotive daily activities. The NEAT score is a possible option for evaluating PAL in daily clinical practice. The present results indicated that non-locomotive activity may have a greater impact on PAL than locomotive activity in COPD patients.

Reference Equations for Assessing the Physical Activity of Japanese Patients with Chronic Obstructive Pulmonary Disease

Background

To improve physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD), providing a target PA value based on the individual patient's condition may be a useful interventional strategy. However, to determine the target value, a predictive PA value for each patient is required.

Research Question

What is the reference equation consisting of PA-related factors to determine the predictive PA value for each patient with COPD?

Material and Methods

In this prospective cross-sectional observational study, we measured the PA with a triaxial accelerometer and several other factors including demographic factors, pulmonary function, dyspnea, exercise capacity, muscle strength, nutrition, and indicators of several comorbidities in stable Japanese outpatients with COPD aged ≥40 years old and detected PA-related factors by a multiple regression analysis and stepwise method. We created reference equations for four indices of PA using multiple linear regression equations.

Results

Two hundred and twenty-seven patients were registered. The equations of duration at ≥2.0 metabolic equivalents (METs) and step count consisted of 4 factors: 6-minute walk distance, modified Medical Research Council dyspnea scale, anxiety score of the Hospital Anxiety and Depression Scale, and the forced expiratory volume in 1 second % of predicted value. Those of duration at ≥3.0 METs and total activity at ≥3.0 METs consisted of 5 factors: the above 4 factors and age or brain natriuretic peptide. There was no fixed bias or proportional bias between the measured and predictive values in patients with non-high measured PA values.

Conclusion

We determined reference equations for four indicators of PA using PA-related factors in Japanese patients with COPD. The predictive values calculated using the equations could be useful for deciding target PA values for each patient.

Clinical Trial Registration

UMIN-CTR; No.: UMIN000025459; URL: https://www.umin.ac.jp/ctr/index.htm.

Longitudinal Relationship Between Growth Differentiation Factor 11 and Physical Activity in Chronic Obstructive Pulmonary Disease

BACKGROUND

Daily physical activity is reduced in patients with chronic obstructive pulmonary disease (COPD) and a reduced level of physical activity has been shown to be an important predictor for the prognosis, such as increased risk of exacerbation and mortality. However, there has not yet been a useful biomarker of the physical activity. In our previous cross-sectional study, we showed that the level of one of the possible myokines, which is an anti-aging factor, growth differentiation factor 11 (GDF11), was decreased in the plasma from patients with COPD and correlated with the physical activity. To clarify this relationship, we conducted a longitudinal evaluation of such factors.

PATIENTS AND METHODS

Twenty-four COPD patients were enrolled and prospectively followed. We measured the levels of plasma GDF11 and systemic inflammatory markers with immunoblotting or ELISA, respectively. We also evaluated lung function and daily physical activity using a triaxial accelerometer and the incidence of exacerbation.

RESULTS

The change in the plasma level of GDF11, but not systemic inflammatory markers, was positively correlated with the change in the physical activity in an intensity-dependent manner (between the change in the number of steps and GDF11; r = 0.41, p = 0.047). In the multiple regression analysis, the relationship was confirmed (β = 0.93, p < 0.001). In addition, patients who maintained their plasma level of GDF11 showed a significantly lower incidence in exacerbations of COPD than those with decreased levels of GDF11 (p = 0.041).

CONCLUSION

The longitudinal change in the plasma level of GDF11 was positively correlated with the change in the daily physical activity in COPD. GDF11 could be a useful humoral factor that reflects the physical activity in COPD.

A Non-Interventional, Cross-Sectional Study to Evaluate Factors Relating to Daily Step Counts and Physical Activity in Japanese Patients with Chronic Obstructive Pulmonary Disease: STEP COPD

Purpose

Patients with chronic obstructive pulmonary disease (COPD) have decreased physical activity (PA) compared with healthy adults. As lower PA is associated with increased mortality, improving PA is an important objective for COPD management. This large-scale, multicenter, non-interventional, cross-sectional study examined the activity status of COPD patients in Japan and explored factors related to PA.

Patients and Methods

Outpatients aged ≥40 years with confirmed COPD diagnosis and pulmonary function test data were enrolled. Primary study outcomes were measurement of daily steps (over 14 consecutive days, using an activity monitor), assessment of activity time by activity intensity (using metabolic equivalents [METs]), and evaluation of correlation between PA and patient characteristics. Secondary outcomes included further investigation of the influence of patient characteristics on PA.

Results

Data from 417 patients with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages I (29.5%), II (43.9%), III (23.5%), and IV (3.1%) were evaluated. Median (Q1, Q3) daily step count was 3440.8 (1831.3, 5709.3). Median (Q1, Q3) durations of PA at ≥3 (moderate-to-vigorous) and ≥2 METs (light-to-vigorous) were 18.7 (6.5, 41.3) and 186.9 (126.9, 259.2) minutes, respectively. For >30% of patients, time spent in ≥3 METs activity was ≤10 minutes. Unemployment was significantly correlated with reduced activity time (≥3 and ≥2 METs) and step count. Severe GOLD stage was significantly correlated with reduced activity time (≥3 and ≥2 METs). High modified Medical Research Council (mMRC) dyspnea score was significantly correlated with reduced activity time (≥3 METs) and step count. Patients tended to overestimate the time spent in activities requiring ≥2 METs in their subjective reports compared with activity monitor measurements.

Conclusion

Reduced PA was observed in the Japanese COPD patients with the majority of them being GOLD stage I/II. Employment status, GOLD stage, and mMRC dyspnea score could help identify patients at risk of reduced PA.

Clinical Trial Registration

NCT03642613 (ClinicalTrials.gov); UMIN000032962 (UMIN-CTR, umin.ac.jp).

The relationships between three-axis accelerometer measures of physical activity and motor symptoms in patients with Parkinson's disease: a single-center pilot study

Background

Various wearable devices for objectively evaluating motor symptoms of patients with Parkinson’s disease (PD) have been developed. Importantly, previous studies have suggested protective effects of physical activity in PD. However, the relationships between conventional clinical ratings for PD and three-axis accelerometer measures of physical activity (e.g., daily physical activity levels [PAL] or metabolic equivalents of task [METs]) are still unclear, particularly for METs. In the current study, we sought to elucidate these relationships on a daily basis, and to clarify optimal predictors for clinical states on a 30-min basis.

Methods

Patients who were hospitalized for adjustment of drugs or deep brain stimulation were enrolled. Using waist-worn three-axis accelerometers, PAL and METs parameter data were obtained and compared with UPDRS-3[On] and symptom diary data. We extracted data from the patients’ best and worst days, defined by the best and worst UPDRS-3[On] scores, respectively. Thus, 22 data sets from 11 patients were extracted. We examined the correlations and produced scatter plots to represent the relationships, then investigated which METs parameters and activity patterns were the best predictors for “On” and “dyskinesia”.

Results

The parameter “mean METs value within the 95–92.5 percentile range on a day (95–92.5 percentile value)” exhibited the strongest correlation with conventional daily clinical ratings (Rho: − 0.799 for UPDRS-3[On], 0.803 for On hours [p < 0.001]). Scatter plots suggested that PAL tended to have higher values in patients with involuntary movement. However, METs parameters focusing on higher METs seemed to alleviate this tendency. We clarified that “time over 2.0 METs” and “time over 1.5 METs” could be predictors for “On” and “dyskinesia” on a 30-min basis, respectively (AUROC: 0.779 and 0.959, 95% CI: 0.733–0.824 and 0.918–1.000). The specificity and sensitivity of the optimal activity pattern for “On” were 0.858 and 0.621.

Conclusions

This study suggested feasible activity patterns and METs parameters for objective evaluation of motor symptoms on a 30-min or daily basis. Three-axis accelerometer measures focusing on higher METs may be appropriate for evaluating physical activity. Further larger-scale studies are necessary to clarify the validity, reliability, and clinical utility of these objective measures.

A Novel Role of Growth Differentiation Factor (GDF)-15 in Overlap with Sedentary Lifestyle and Cognitive Risk in COPD

Sedentary behavior and cognitive impairment have a direct impact on patients' outcomes. An energy metabolic disorder may be involved in the overlap of these comorbid conditions (motoric cognitive risk (MCR)) in patients with chronic obstructive pulmonary disease (COPD). We aimed to explore the linkage between a proapoptotic protein, growth differentiation factor (GDF)-15, and MCR. Physical activity (PA), cognitive function (Japanese version of the Montreal Cognitive Assessment: MOCA-J), and the serum GDF-15 levels were assessed in healthy subjects (n = 14), asthmatics (n = 22), and COPD patients (n = 28). In the entire cohort, serum GDF-15 had negative correlations with exercise (Ex) (ρ = -0.43, p < 0.001) and MoCA-J (ρ = -0.44, p < 0.001), and Ex and MOCA-J showed a positive correlation (ρ = 0.52, p < 0.0001). Compared to healthy subjects and asthmatics, COPD patients showed the highest serum GDF-15 levels and had a significantly higher proportion of subjects with MCR (both sedentary lifestyle (EX < 1.5) and cognitive risk (MoCA-J ≤ 25)). Also, we found that serum GDF-15 has a screening potential (100% sensitivity) greater than aging (67% sensitivity) for detecting MCR in COPD patients. In conclusion, higher serum GDF-15 had interrelationships with a sedentary lifestyle and cognitive risk. This protein was not disease-specific but could be a screening biomarker to detect MCR related to poor health outcomes of COPD patients.

Simple standard equation for daily step count in Japanese patients with chronic obstructive pulmonary disease

Purpose

The improvement of physical activity in patients with COPD is an important issue. However, no standard for the recommended number of steps for patients with COPD has been determined. We conducted a retrospective observational study to create a simple standard equation for the daily step count, which makes it easier to determine whether each subject is attaining his/her predicted value or not.

Patients and methods

Stable outpatients diagnosed with COPD whose physical activities had been measured using a triaxial accelerometer for more than 2 weeks were recruited from 5 institutes in Japan. Factors associated with the step count were detected by multivariate regression analysis. After the data were transformed to a normalized distribution, a multivariate linear regression equation was created using stepwise regression.

Results

One hundred sixty-two patients aged 72.3 (7.2) years and of FEV1 %pred 59.2 (22.8) % were recruited. Among the parameters, age, mMRC dyspnea scale and inspiratory capacity (IC) were detected by the stepwise method. The created standard equation was “Step count = (−0.079×[age]−1.595×[mMRC]+2.078×[IC]+18.149)³”. The correlations between the calculated values and the measured values were observed, and fixed, and proportional biases between them were also observed. When patients with <6500 steps/day were selected, no systematic bias between them could be detected.

Conclusion

A simple standard equation for Japanese patients with COPD was created using age, mMRC and IC, and could provide an individual-predicted value, especially for patients with <6500 steps/day.

Combination of assist use of short-acting beta-2 agonists inhalation and guidance based on patient-specific restrictions in daily behavior: Impact on physical activity of Japanese patients with chronic obstructive pulmonary disease

BACKGROUND

Assist use of inhaled short-acting beta 2 agonists (SABAs) is reportedly effective for preventing shortness of breath on exertion in chronic obstructive pulmonary disease (COPD) patients. However, it is unclear what strategy would be useful for improving physical activity in such patients. The aim is to investigate the effects of assisted use of SABA (procaterol) on physical activity in Japanese COPD patients targeting patient-specific restrictions in daily behavior.

METHODS

Fourteen patients with stable COPD (age: 72.1±1.5, %FEV₁: 55.6±4.5%) were asked to inhale 20 μg of procaterol 15 minutes before patient-specific daily physical activity that had been identified as limited by a questionnaire and document their usage in a diary. Physical activity was measured using a triaxial accelerometer and the results were collected every month for 2 months. In the first month, a clinician assessed whether inhalation of SABA was appropriate based on a usage diary and coached patients to conduct adequate assist use of SABA for limited physical activity.

RESULTS

The strategy significantly improved the physical activity level, assessed using the values of the metabolic equivalents (METs) multiplied by physical activity endurance, at ≥3.0 METs (p<0.05), and physical activity endurance at ≥2.5 and ≥3.0 METs, (p<0.05, p<0.05, respectively). The degree of improvement of physical activity level was significantly positively correlated with the baseline %FVC and %FEV₁ (p<0.05, p<0.05, respectively).

CONCLUSIONS

Assist use of SABA targeting patient-specific restrictions, particularly when better lung function is still preserved, could be a useful approach for improving physical activity in patients with COPD.

Factors influencing the physical activity in daily life of male patients with different levels of severity of chronic obstructive pulmonary disease

[Purpose] Physical activity influences the prognosis of chronic obstructive pulmonary disease and is influenced by exercise tolerance, and environmental, psychological, and many other factors, but the influence of these factors on physical activity levels in each stage of chronic obstructive pulmonary disease is unknown. This study aimed to clarify this matter. [Participants and Methods] Seventy-one male patients with chronic obstructive pulmonary disease (aged 72.2 ± 4.5 years) participated in this study. We compared physical activity levels (determined as daily steps), presence or absence of daily routine (e.g., housework or hobby), 6-minute walking distance, psychological factors (using the Hospital Anxiety and Depression Scale), and health-related quality of life (Physical and Mental component summary of the 36-item short-form health survey) between patients in different stages of chronic obstructive pulmonary disease. [Results] When examined at each stage of chronic obstructive pulmonary disease, physical activity levels correlated with the presence or absence of daily routine, 6-minute walking distance, and Physical component summary in all stages, but the scores in the anxiety and depression components of the Hospital Anxiety and Depression Scale and Mental component summary correlated only with stage 4. [Conclusion] Physical functioning was related to physical activity levels at any stage of chronic obstructive pulmonary disease, although psychological functioning was related to the progress of disease severity. The approach to promote an active lifestyle must be selected depending on the stage of chronic obstructive pulmonary disease.

Physical inactivity is associated with decreased growth differentiation factor 11 in chronic obstructive pulmonary disease

BACKGROUND

Growth differentiation factor 11 (GDF11) is reported to possess anti-aging and rejuvenating effects, including muscle regeneration and to be highly expressed in skeletal muscle. Recently, we demonstrated that the levels of plasma GDF11 were decreased in COPD. However, the effect of decreased circulating GDF11 in the pathophysiology of COPD remains unknown. The aim of this study is to investigate the association between the plasma GDF11 levels and various clinical parameters in patients with COPD.

PATIENTS AND METHODS

Eighteen ex-smokers as control subjects and 70 COPD patients participated in the current study. We measured the levels of plasma GDF11 using immunoblotting, lung function, physical activity using a triaxial accelerometer, quadriceps strength, exercise capacity, and systemic inflammatory markers. We investigated the association between the levels of plasma GDF11 and these clinical parameters.

RESULTS

The levels of plasma GDF11 in the COPD patients had significant positive correlations with the data of lung function. Furthermore, the levels of plasma GDF11 were significantly correlated with the physical activity, quadriceps strength, and exercise capacity. Moreover, the levels of plasma GDF11 were significantly correlated with the data of inflammatory markers. Although various factors were related to GDF11, the multiple regression analysis showed that physical activity was significantly associated with the levels of plasma GDF11.

CONCLUSION

Physical inactivity was significantly related to the decreased GDF11 levels in COPD, which might be useful for understanding the pathogenesis of COPD. Clarifying the relationships between the physical inactivity and GDF11 may reveal a potentially attractive therapeutic approach in COPD via increasing the plasma levels of GDF11.

Verification of a Motion Sensor for Evaluating Physical Activity in COPD Patients

Background

Objective evaluation of the physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD) is important. We validated a triaxial accelerometer, Active Style Pro HJA-750C® (HJA), and evaluated the necessary conditions for obtaining reproducible data.

Methods

The PA measured by HJA was compared with that measured by two already validated accelerometers in 11 patients with COPD (age: 76.6 ± 6.9, FEV1% predicted: 57.6 ± 18.6). Then, the influence of weather and holidays on the PA and the required number of days to obtain repeatability were examined in 21 patients with COPD (age: 73.0 ± 8.0, FEV1% predicted: 58.7 ± 19.0).

Results

The PA values measured by HJA and those by DynaPort Move Monitor® (DMM) or Actimarker® (AM) were significantly correlated at all intensities (p=0.024 at ≥4.0 METs by DMM and p < 0.0001 at the rest) except at ≥4.0 METs by AM, though the values measured by HJA were higher than those by AM which was reported to underestimate PA. The durations of PA on rainy days were significantly shorter than those on nonrainy days, but those on holidays were not different from those on weekdays. The values of ICC for 3, 4, or 5 days were higher than 0.8 at all intensities. The PA measured by HJA was correlated with the dyspnea scale FVC and age and tended to correlate with FEV1.

Conclusions

The HJA was validated for evaluating the PA in patients with COPD. This trial is registered with UMIN000016363.

Study Design of VESUTO®: Efficacy of Tiotropium/Olodaterol on Lung Hyperinflation, Exercise Capacity, and Physical Activity in Japanese Patients with Chronic Obstructive Pulmonary Disease

Introduction

The superiority of tiotropium/olodaterol is demonstrated in improvement of lung function, dyspnea, lung hyperinflation, and quality of life compared with either monotherapy in patients with chronic obstructive pulmonary disease (COPD). Japanese Respiratory Society Guidelines for COPD management include improvement of exercise tolerance and daily physical activity as the treatment goals; however, there is limited evidence in Japanese patients with COPD.

Methods

A protocol is developed for the VESUTO^® study that investigates the efficacy of tiotropium/olodaterol fixed-dose combination (FDC) compared with tiotropium alone on inspiratory capacity (IC, volume from functional residual capacity to total lung capacity), exercise capacity, and daily physical activity in Japanese patients with COPD.

Results

A total of 180 Japanese patients with COPD, aged ≥40 years will be enrolled into the double-blind, multicenter, active-controlled, crossover study (NCT02629965) and will be randomized to receive either tiotropium/olodaterol FDC or tiotropium for 6 weeks each [two puffs via RESPIMAT^® (Boehringer Ingelheim, Ingelheim, Germany) inhaler in the morning]. The primary endpoint is IC at rest measured at 60 min post-dose after 6 weeks treatment. The secondary endpoints include the 6-min walk distance (6MWD) at 90 min post-dose and physical activity measured by the activity monitor in the last 2 weeks of the 6-week treatment periods. Lung function tests will also be assessed after 6 weeks treatment. A mixed-effects model repeated measures approach will be used for the primary and secondary endpoints.

Conclusion

The VESUTO^® study is the first randomized interventional study to investigate exercise capacity (6MWD) and physical activity measured by a 3-axis accelerometer in Japanese patients with COPD. The study could provide additional evidence of long-acting muscarinic antagonist (LAMA) + long-acting β₂-agonist (LABA) combination therapy on patients’ physical activities as well as lung function.

Trial registration

ClinicalTrials.gov: NCT02629965 (registered on December 1, 2015).

Funding

The VESUTO study was funded by Nippon Boehringer Ingelheim Co., Ltd., Tokyo, Japan.

Electronic supplementary material

The online version of this article (doi:10.1007/s12325-017-0554-3) contains supplementary material, which is available to authorized users.

Differences in physical activity according to mMRC grade in patients with COPD

BACKGROUND

Physical activity (PA) is impaired from the early stages of COPD, is associated with a worsening of disease prognosis, and causes COPD patients to restrict their daily activities in order to avoid breathlessness. The development of a simple tool to estimate physical activity level (PAL) could be useful for the management of COPD.

OBJECTIVES

We investigated the differences in PA according to the modified Medical Research Council (mMRC) grade in patients with COPD.

METHODS

A cross-sectional study was performed on stable outpatients with COPD. PA was measured for 2 weeks using a triaxial accelerometer, and dyspnea grade was evaluated in all patients using the mMRC scale.

RESULTS

Ninety-eight patients were recruited. Significant differences in PA duration were observed at all intensities according to the mMRC grade. Despite treatment with controller medications, 59.2% of COPD patients had low PAL, which was <1.5 metabolic equivalents multiplied by hour per day. COPD patients with an mMRC grade ≥2, which was the most balanced cutoff point in the receiver operating characteristic curve, showed a higher reduction rate of PAL (80.0% at mMRC grade 2, 71.4% at mMRC grade 3, and 100% at mMRC grade 4).

CONCLUSION

PA differed according to the mMRC grade, and mMRC grade ≥2 could predict a low PAL. Therefore, assessment of breathlessness by the mMRC questionnaire would be useful to stratify the risks of reduced PA in COPD.

Effects of pharmacologic treatment based on airflow limitation and breathlessness on daily physical activity in patients with chronic obstructive pulmonary disease

BACKGROUND

Improvement in the daily physical activity (PA) is important for the management of chronic obstructive pulmonary disease (COPD). However, the effects of pharmacologic treatment on PA are not well understood. We evaluated the effects of additional medications, including bronchodilator with or without inhaled corticosteroid, based on airflow limitation and breathlessness on the PA in COPD patients and the factors that could predict or affect the improvement in PA.

METHODS

A prospective non-randomized observational study was employed. Twenty-one COPD subjects without any other diseases that might reduce PA were recruited. The PA was measured with a triaxial accelerometer for 2 weeks, and pulmonary function tests and incremental shuttle walking tests were administered before and after 4-week treatment with an additional medication.

RESULTS

Bronchodilation was obtained by additional medication. The mean values of PA evaluated by metabolic equivalents (METs) at ≥3.0 METs and the duration of PA at ≥3.0 METs and ≥3.5 METs were improved by medication. The % change in the duration of PA at ≥3.5 METs was significantly correlated with the baseline functional residual capacity (FRC), residual volume, and inspiratory capacity/total lung capacity. However, the % change in the duration of PA at any intensity was not correlated with the % changes of any values of the pulmonary function tests or incremental shuttle walking test except the PA at ≥2.5 METs with FRC.

CONCLUSION

Medication could improve the PA in patients with COPD, especially at a relatively high intensity of activity when medication was administered based on airflow limitation and breathlessness. The improvement was seen in the patients with better baseline lung volume, but was not correlated with the improvements in the pulmonary function tests or exercise capacity.

Influence of indacaterol on daily physical activity in patients with untreated chronic obstructive pulmonary disease

Background

Indacaterol, a once-daily, long-acting β₂-agonist, may improve not only respiratory function, dyspnea symptoms, and quality of life, but also physical activity for patients with chronic obstructive pulmonary disease (COPD). This study aimed to evaluate the effect of 12-week indacaterol therapy on daytime physical activity in patients with untreated COPD.

Methods

The subjects were stable and untreated COPD outpatients with a percent predicted forced expiratory volume in 1 second (%FEV₁) below 80%. Baseline assessments included clinical assessment, respiratory function testing, arterial blood gas analysis, the COPD assessment test (CAT™), and the Medical Outcomes Study 36-Item Short-Form Health Survey, Japanese version 2 (SF-36v2^®). Patients underwent monitoring by uniaxial accelerometer before and after 12 weeks once-daily inhalation of indacaterol 150 μg/day.

Results

Eighteen patients were evaluable. Patient characteristics included a mean age of 74.2 years, and three patients were current smokers. Indacaterol improved mean (± standard deviation [SD]) %FEV₁ from 55.2% (±17.9%) to 61.0% (±17.3%) (P=0.003), CAT scores from 16.4 (±10.2) points to 12.4 (±8.2) points (P=0.04), some scales of the SF-36v2 (physical component summary, 41.6±9.7 points to 45.1±7.9 points, P=0.03), and number of daily steps (3,311.5±2,103.3 steps/day to 3,841.8±2,096.8 steps/day, P=0.02), but did not affect daily energy expenditure (85.0±77.2 kcal change to 90.9±56.8 kcal, P=0.29) or exercise duration of an intensity of level 1 or more (36.4±23.9 minutes increase to 40.8±21.6 minutes, P=0.12).

Conclusion

Twelve weeks of indacaterol improved respiratory function and quality of life, but did not significantly affect physical activity in patients with moderate-to-severe COPD.